1. Field of the Invention
This invention pertains to automatic stove top fire extinguishing systems in general and, more particularly, to a means of supplying slack to a cable in the event of a fire in order to automatically activate the extinguishing system.
2. General Background
Many devices currently exist that pertain to the automatic extinguishing of stove top fires. Typical examples of such systems are shown in U.S. Pat. No. 5,127,479 issued to Stehling et al., and U.S. Pat. No. 4,773,485 issued to Silverman. In both of these examples, a fire extinguisher is installed in a hood positioned above the stove top. Piping or tubing is secured to the discharge nozzle of these fire extinguishers which lead to release or exit ports located above the most likely place for a fire on the stove top. The control handle of these fire extinguishers are biased in the operable position, but held inoperable by a cable system. The cable system itself contains a series of exposed segmented cables all held together by equally exposed fusible or reusable heat-activated links distributed above the stove top. Thus, upon the occurrence of a fire, these fusible links melt, thereby releasing the cable that holds the control handle of the fire extinguisher in the inoperable position. Upon the release of the cable, the fire extinguisher is allowed to discharge its contents which travel through the piping or tubing and out the exit ports onto the stove top or fire.
An improvement to the system disclosed above is shown in U.S. Pat. No. 5,297,636 issued to North. This system operates in a similar manner but it also includes the feature of automatically closing the valve that supplies gas to the stove burners in the event of a fire.
Alternate versions of extinguishing stove top fires are shown in U.S. Pat. No. 3,584,688 issued to Duncan et al. and U.S. Pat. No. 4,580,638 issued to Jones et al. While these versions also rely upon a series of exposed segmented cables held together by equally exposed fusible links, the fire extinguishing material is contained in a stand-alone structure some distance from the stove.
While all of the above methods would seem to be operable, there is always the possibility that over time their exposed fusible links may carbonize or accumulate a layer of hardened grease which may catastrophically affect their operation in a time of need. Additionally, the exposed segmented cables of such a system may also become encrusted with grease or other matter, thereby affecting their operation, such as by restricting the ability of the cable to freely bend around its pulleys or slide along its guides. Also, since both the fusible links and the cables are exposed, it is also possible that the system will accidently become tripped during routine cleaning.